Internal combustion engines are commonly used to power small watercraft such as personal watercraft. These watercraft include a hull which defines an engine compartment. The engine is positioned in the engine compartment. The output shaft of the engine is coupled to a water propulsion device of the watercraft, such as an impeller.
Air must be supplied to the engine from outside the hull for use in the combustion process. Typically, air flows through one or more ducts in the hull into the engine compartment, and then through an intake system of the engine to the combustion chamber(s) thereof.
Fuel is also supplied to the engine for use in the combustion process. In order to accurately meter the fuel and improve engine operating efficiency and performance, the fuel is injected with one or more fuel injectors. In this arrangement, fuel is supplied to the fuel injectors at high pressure. Each injector has an electrically operated valve which selectively opens and closes, controlling the flow of fuel therethrough to the engine.
One problem associated with this arrangement is that water may contact the injector and damage it. In particular, water often flows with the air through the intake ducts into the engine compartment. This water may directly flow onto the injector, or pools in the bottom of the hull and splashes about due to the pitching and rocking movement of the watercraft as it moves through the water. When the water sprays or splashes onto the fuel injector, it may corrode the injector and interrupt the electrical current flowing thereto and controlling the injector. This may result in damage to the injector and may affect the operation of the engine.
In order to keep the size of the watercraft small and the center of gravity low, the engine compartment is made very small, thus necessitating that the engine be compact. One problem with this arrangement is that hot exhaust gasses flowing through the exhaust system from the engine may be routed very closed to other components of the engine, damaging them or resulting in their poor performance. This is true of the fuel injectors, where the heat from the exhaust system may damage the injector and shorten its useful life.
An improved fuel injector arrangement for an engine of the type utilized to power a small watercraft, such as a personal watercraft, is desired.